Download How do we add using expanded form? Lesson 4 Expanded

Lesson
4 Expanded Addition
Problem Solving:
Using Bar Graphs to Display Data
Expanded Addition
Vocabulary
How do we add using expanded form?
expanded addition
Remember that we model addition with place-value coins.
Look at how the numbers 43 and 26 are shown with the coins.
Tens
We can use the coins to help us find the sum of the numbers
43 and 26. We add the ones coins from both numbers, then
we add the tens from both numbers.
When we add numbers in expanded form, we use
expanded addition . There are steps to solving problems in
expanded addition.
Ones
10
10
10
10
1
10
10
1
1
1
43
1
1
+ 26
1
1
1
Example 1
Add using expanded addition.
Step 1
Write the addition problem
in expanded form.
Now, we can add by place value
like we did with the coins.
Step 2
Add the ones column.
Then add the tens column.
40 3
43
+ 26 S + 20 6
40 3
+ 20 6
9
40 3
+ 20 6
60 9 = 60 + 9
Step 3
Write the sum in standard form. 60 + 9 = 69 The sum is 69.
Apply Skills
Turn to Interactive Text,
page 13.
Reinforce Understanding
Use the mBook Study Guide
to review lesson concepts.
Unit 1 • Lesson 4 19
Lesson 4
Problem Solving: Using Bar Graphs to Display Data
What are bar graphs, and how are they used?
Data can be displayed in many different ways. One common way to
present data is with a bar graph . In this lesson, we begin following
the CD sales of a band called The Scatter Plots by looking at the bar
graph below.
Vocabulary
bar graph
title
horizontal axis
vertical axis
scale
interval
Number of CDs Sold
The title of the bar graph tells
us that the graph shows the
CD sales for the Scatter Plots
from January through April.
The Scatter Plots CD Sales
January–April
500
400
300
200
100
0
January
February
March
Month
The line along the left side of the graph
labeled Number of CDs Sold is the vertical
axis . Notice the numbers along this axis:
0, 100, 200, 300, 400, and 500. This is
the scale of the graph. The numbers in the
scale are changing by 100, so the interval of the scale is 100.
20 Unit 1 • Lesson 4
April
The line across the bottom of
the graph labeled Month is
the horizontal axis .
Lesson 4
The bar graph shows how many CDs the Scatter Plots sold over a period
of four months:
Month
January
February
March
April
CDs Sold
100
200
300
400
Understanding Scale and Interval
It is important to understand the scale of the graph. Notice the scale
of the bar graph ranges from 0 to 500, and the interval is 100. We can
think of this as counting by 100 from 0 to 500.
This scale and interval were selected because they do a good job of
representing the data shown in the graph.
Problem-Solving Activity
Turn to Interactive Text,
page 14.
Pay close attention
to the scale and
the interval.
Reinforce Understanding
Use the mBook Study Guide
to review lesson concepts.
Unit 1 • Lesson 4 21
Lesson 4
Homework
Activity 1
Write the number in expanded form.
Model 49 40 + 9
1.
35
2.
529
3.
812
4.
375
5.
16,020
6.
45,999
7.
6,015
8.
4,007
Activity 2
Add using expanded addition. Then write the sum in standard form.
Model
28
20 8
​
+ 61 S + 60 1
80 9
80 + 9 Answer= 89
1.
17
+ 82
2.
45
+ 33
3.
54
+ 22
4.
61
+ 16
5.
32
+ 25
6.
40
+ 49
Activity 3
Copy and complete the chart of basic and extended facts.
Basic Fact
2+4
Extended Fact
(Basic Fact × 10)
20 + 40
20 + 80
9+1
2+7
Extended Fact
(Basic Fact × 100)
200 + 400
900 + 100
200 + 700
30 + 30
9+8
600 + 500
Activity 4 • Distributed Practice
Add.
22 1.
2+3
2.
20 + 30
3.
200 + 300
4.
2,000 + 3,000
5.
7+4
6.
700 + 400
Unit 1 • Lesson 4